尾静脉注射碘酸钠对小鼠视网膜形态结构变化的影响

Effect of sodium iodate on morphological and structural changes of retina in mice

目的探讨尾静脉注射碘酸钠(NaIO3)对小鼠视网膜形态结构的影响。方法36只昆明小鼠分为4组对照组、损伤3 d组、损伤7 d组、损伤14 d组。对照组不作任何处理,各损伤组小鼠经尾静脉单剂量注射NaIO3(35 mg·kg-1)。在NaIO3损伤3 d、7 d、14 d后取材,进行视网膜组织铺片和组织切片。利用HE染色、NeuN免疫组织化学染色及Opn1mw、GFAP、Iba1免疫荧光染色,检测NaIO3注射后不同时间小鼠视网膜形态结构的改变。结果HE染色结果显示,损伤3 d后外核层每10μm长度细胞数由正常水平(31.97±2.27)个下降至(26.21±0.83)个,差异有统计学意义(P<0.05);损伤7 d后内核层每10μm长度细胞数由正常水平(12.33±0.16)个下降至(11.39±0.43)个,差异有统计学意义(P<0.05)。NeuN染色结果显示,损伤14 d后视网膜神经节细胞层每100μm长度视网膜神经节细胞数由正常水平(14.92±1.74)个下降至(11.25±0.09)个,差异有统计学意义(P<0.05)。GFAP染色结果显示,损伤3 d组每200μm×200μm范围内活化的Müller细胞数由对照组的(16.96±0.85)个增加至(20.42±1.64)个,差异也有统计学意义(P<0.05)。Opn1mw、Iba1染色结果显示,损伤后视网膜视锥细胞外节段变薄、小胶质细胞数增加。结论尾静脉注射NaIO3会引起小鼠视网膜形态结构不可逆的损伤,且该损伤具有时间依赖性。

Objective To investigate the effect of the sodium iodate(NaIO3)on retinal morphology injected into mice via the tail vein.Methods Totally 36 Kunming mice were divided into 4 groupscontrol group,NaIO3-injected on day 3 group,day 7 group,day 14 group.The control group received no treatment,and the NaIO3-injected group mice received NaIO3(35 mg·kg-1)in a single dose via the tail vein.After 3,7,and 14 days,retinal tissue was laid and sectioned.Retinal morphology was assessed at different NaIO3-injected time points via HE staining,NeuN immunohistochemical staining,Opn1mw,GFAP and Iba1 immunofluorescence staining.Results HE results shown that,after NaIO3-injected 3 days,the cells number per 10μm in outer nuclear layer were reduced from(31.97±2.27)to(26.21±0.83)(P<0.05);and after NaIO3-injected 7 days,the cells number per 10μm in inner nuclear layer were reduced from(12.33±0.16)to(11.39±0.43)(P<0.05).NeuN staining shown that,after NaIO3-injected 14 days,the cells number of retinal ganglion cell per 100μm were reduced from(14.92±1.74)to(11.25±0.09)(P<0.05).GFAP staining showed that,after NaIO3-injected 3 days,the number of GFAP-positive astrocytes per 200μm×200μm were increased from(16.96±0.85)to(20.42±1.64)(P<0.05).According to the staining results of Opn1mw and Iba1,the outer segments of cones became thinner,as well as the number of microglia cell was significantly increased after NaIO3-injected.Conclusion A single dose(35 mg·kg-1)of NaIO3 can cause irreversible,time-dependent morphological and structural damage of the retina in mice.